Fix: Serial TTY Terminal Output on Raspberry Pi 3 is Garbled, Garbage or Otherwise Broken

 Saturday, March 19, 2016
Problem
You've prepped your Raspbian SD card. You've plugged in your FTDI / RS232 adapter to your shiny new Raspberry Pi 3, set up Putty for 115200, Parity 8, Flow Control None, Stop. You've wired everything correctly, Ground to Ground, Tx to Rx, Rx to Tx, and you plug-in, only to be greeted by garbage. Lots of garbage. Blocks, Corners, non-English characters. It looks like your modem looked when it blew off a BBS connection in 1992. But it was just dandy with your Raspberry Pi 2! What gives?
What's happening
Bear with me since some of this may be inaccurate. I'll be honest, the last time I dealt with troubleshooting a serial terminal connection was easily 18 years ago. This shouldn't have happened, really. In my teen years, I actually coded a FOSSIL COM driver into Bulletin Board System software I had written for my multi-node BBS (get off my lawn!). 18 years and many lines of code later, I'm feeling senile.
So with serial communication, there's always the sensitive issue of timing. Your Pi is trying to send data at 115200bps. It's failing. Somewhere along the mystical way, the CPU clock rate is set in such a way that it doesn't quite deliver at the right speed and the result is the text vomit you're seeing in PuTTY.
The Fix
The fix is simple, but has side-effects. If you're simply setting up the serial terminal in order to login and configure WiFi because you're too lazy to walk 10 feet to another room and plug in an Ethernet cable, it's a perfect solution. If you are interested in using serial communication for some other purpose, it's not.
Simply plug the SD card into your PC. Open up the "config.txt" in the root in something that will understand the line endings properly (Notepad++, Atom, Visual Studio Code, Sublime, ... basically anything other than Notepad). Insert the line "core_freq=250". Save and safely eject the card. Pop it back into your Raspberry Pi 3 with everything plugged in and you should see the majestic, properly formatted, vomit-free boot sequence. Login and you're good!
Once you're done and network connected, remove that line from the config.txt (located in /boot/config.txt if you're editing directly on your RPi) and reboot. You'll be back to the original, faster clock speed (and broken serial communication).
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HowTo: Add yourself as a local administrator via DirectAccess only connected PC

 Friday, March 18, 2016
Problem
You've just been offline domain joined to your domain and you login with your account only to discover that you're a non-administrator on your laptop! This won't do, so you hop launch Computer Management using a local administrator account or Microsoft Account that's an administrator and try to add your Active Directory ID. You soon discover that though Computer Management thinks it can see the domain, it can't seem to find the account that you're actually logged into the computer with!
Why It Doesn't Work
Honestly, I'm not sure on this one. My hypothesis is that Computer Management launched as a local admin is not able to use the DA tunnel, but it knows you're in a domain and expects that it can get to it. This is backed up by the long (Not Responding) message as you wait for it to fail. Bummer.
The Fix
Use a tool that is so old that it can't possibly fail! Kidding. But it is old. Remember the "net" command?
Launch a Command Prompt (cmd.exe) as a local administrator (or Microsoft Account with Local Administrator access).
Type in:
net localgroup administrators YOURDOMAIN\youraccount /ADD

I believe you're going to have to use your SamAccountName (old style DOMAIN\account) rather than UPN (account@ActiveDirectoryDomain.int), but the latter may work. I didn't try it so I simply don't know. :)
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